“(Leviticus 1:2): “…from animals, from cattle or from the flock.” Blessed be the Omnipresent who told about Himself through the first Tzaddikim, Adam brought a bull on the altar, as it is said (Psalms 69:32): “And it will appeal to the Lord more than a young bull.” Noah kept what was written in the Torah, as it is said, (Genesis 8:20): “And Noah built an altar to the Lord.” Abraham kept the whole Torah, as it is said, (Genesis 26:5): “Because Abraham hearkened,” for he made a sacrifice and brought a ram, Isaac kept what was written in the Torah and flung himself down before his father like a lamb to the slaughter. Jacob kept what was written in the Torah, as it is said, (Genesis 35:4):”And they gave Jacob all the deities of the nations….” (VaYikra Rabbah 2:10)
Three types of animals symbolize the three lines in spiritual work. A person must sort out all of the desires within him and choose the ones that will help him reach the highest work. This is the line of Jacob, the “middle line” that includes within it both plus and minus.
Abraham is Hesed, Isaac is Gevura, and Jacob is Tifferet. For each one of them, there is a suitable Kosher animal, meaning suitable to serve in order to bestow to the Creator through society.
From KabTV’s “Secrets of the Eternal Book” 11/13/13